RheumatoidArthritisSH1 Flashcards
Rheumatoid arthritis
Types of meds
Autoimmune
NSAIDs: not to prevent or slow joint destruction. Helps sx. Used in conjunction with DMARDs
Corticosteroids: great bridge therapy until DMARDs start working
- RAYOS ( prednisone ) delayed release formulation that can be taken at night so RA patients can be not as stiff in am and move joints.
DMARDS
Disease modifying anti rheumatic drugs
• NON - biological DMARDS : should be started within 3 months of dx.
Most start with methotrexate or leflunomide ( arava )
If milder RA can start with hydroxychloroquine or another DMARD
Biological DMARDs : saved for patients who dont respond well to non-biologics
Most start with TNF blocker such as Enbrel, Humira, or Remicade. Patients with poor prognosis may get Orencia, Rituxan
Auranofin ( Ridaura )
1 side effect diarrhea
Gold compounds
Methotrexate side effect
M-mucocytosis
E
T
H- hepatic toxicity
☀️- photosensitivity ; bald head ( alopecia )
T
R- RASH/ Renal ( crystal formations can occur in kidneys so) you want to give bicarbonate to keep that urine alkaline
E
X- x-ray bc watch for pulmonary fibrosis ( watch of cough /SOB ) / PREGnancy category X
A
T
E
And check labs on all DMARDS ( CBC ) -monitoring parameters ( •cbc ( WBC and platelets q4wks, • CXR, •LFT 9q3-4 months) , • renal function )
Methotrexate
•Trexall - PO
•Otrexup; Rasuvo : autoinjector • subQ ( preservative free )
MOA:
- antimetabolite chemo ( cell cycle specific )
-S phase toxin ( DNA synthesis phase )
-Folic acid structural analog
-competitively inhibits DHF reductase
-inhibits de novo pyrimidine synthesis:
Dosing is very important: chemo methotrexate very different than RA or psoriasis
Methotrexate indications
ectopic pregnancy ( category X ) ( “off label use “ )
Psoriasis
Cancer chemo
RA
Dosing for methotrexate for RA
Once weekly!
7.5 mg weekly or 2. 5 mg tabs q12 hours x 3 doses given ( Qweek )
Max 20 mg /week
Folate 1mg /day except the day of MTX
Takes 4 to 6 weeks to get full response ( relatively quick ) but patient may need to be on steroids ( bridge therapy ) until it kicks in those 4 to 6 weeks
DMARD
Disease modifying anti rheumatic drugs
- suppress your own immune system form attacking itself
DDI methotrexate
Contraindications
Bactrim , PPI , NSAIDS , levetiracetam : all increase MTX toxicity
Bactrim - hold bactrim or MTX( trimethoprim component affects hydrofolate so you know it causes immunosupression )
PPI: recommend h2 blocker
NSAIDs/ salicylates: caution
Levetiracetam may increase MTX levels
contraindications : preg category X ( use birth control bc males shouldn’t get someone pregnant as well ) ; renal insufficiency ( creatinine > 1.5 ) ; pleural effusion, active stomatitis, diarrhea or infection, immuno-deficiency ; alcochol use or liver disease ( hepatotoxicity ) ; age> 70 ( as you age renal function goes down )
Methotrexate antidote?
Leucovorin
Leflunomide
Arava
MOA: Pyrimidine inhibitor. Inhibits dihydroorotate dehydrogenases. Inhibitor of T cell activation & proliferation. Similar to MTX in effects and efficacy.
Onset of action : 1 to 2 months
Loading dose: 100 mg po QD for 3 days. Maintenance : 10 - 20 mg once daily
SE
L - LFTs, long half life ( could take up to 2 years for serum conc of drug to be undetectable / LIVER labs
A- alopecia / check ALT/AST every month
Diarrhea
Cholestyramine 8 grams TID x 11 days
To get rid of Leflunomide. Wash out procedure
Say patient wants to get pregnant or another reason. ( preg X )
Can also use activated charcoal
Azathiopurine
IMURAN
MOA: purine analog / Antimetabolite converts to 6MP
Azathiopurine and 6MP needs xanatnine oxidase to be metabolized. ( allopurinol xanathine oxidase inhbitor )
If you add allopurinol / febuxostat ( uloric ) : you worry about azathiopurine or 6MP toxicity so decrease dosage of 6MP or imuran
Preg category D
Indication: RA, renal transplantation
Dosing : 100 mg PO qd; 1-2mg/kg/day
Contraindications
Azathioprine
IMURAN
- if it works on s phase so it can cause myelosuppresion.
All DMARDs cause myelosuppresion : check CBC
D-Penicillamine
( cuprimine ) - COPPER
Never first line for RA
Used for RA and can be used Wilson’s disease ( too much copper in system ) / used for lead poisoning.
Penicillins on empty stomach
D-penicillamine on empty stomach
DMARD SE
Myelosuppresion,
GI
Renal
Contraindications : myasthenia gravis,